DE102006030228A1 - Household appliance and pull-out system for a household appliance - Google Patents

Abstract

A household appliance, in particular a cooking appliance, has at least two mutually relatively movable contact elements (29, 37), which are at least partially in contact with each other, wherein at least one contact element comprises a coating (33). An extension system (13) has rolling elements (29) which are arranged in a rolling element cage (37), wherein at least the rolling element cage (37) has a coating (33). In the household appliance and in the pull-out system (13), the coating (33) has at least one polyether ketone, PEK.

Description

The The invention relates to a household appliance, in particular cooking appliance, with at least two mutually relatively movable contact elements, at least partially in contact with each other, wherein at least one contact element includes a coating. The invention further relates to extraction system for a Home appliance, wherein the extraction system has rolling elements, arranged in a Wälzkörperkäfig are at least the Wälzkörperkäfig a Coating has.

State of the art

From the introduction to the description of DE 198 59 986 A1 is a generic extraction system known. The pull-out system has a stationary inner rail and a movable outer rail. The movable outer rail is supported by balls on the stationary inner rail. The balls are rotatably supported in a ball cage. The cage can be made from a material having high temperature and good sliding properties, which is a combination of plastic and carbon.

Out EP 0 994 309 A2 is a pull-out device is known, which partially has a cooking chamber pull-out rails. These are slidably guided in stationary guides. The rails and / or the guides are provided at least on their sliding surfaces with a sliding material.

Out DE 102 11 470 A1 a generic pull-out system is known which has a stationary inner rail, a movable intermediate rail and a movable outer rail. The rails are provided with an easy-to-clean PTFE-based coating. Depending on the accessibility of the rails or components for food and / or the user different coating qualities are provided. Thus, component areas that point downwards can be equipped with a lower coating quality with regard to cleanability and / or abrasion resistance than component areas facing upwards, which are exposed directly to product spills.

Out DE 199 49 239 A1 is a pull-out device, in particular telescopic extension device, known, are guided in the rails by means of ball bearings or roller bearings on stationary guides. The balls of the ball bearings or the rollers of the roller bearings consist at least on their surface of a self-lubricating material.

Out DE 38 15 440 a telescopic insertion device is known, which is designed as a telescopic extension with a stationary inner rail, a rollable middle rail and a rollable outer rail for the food support. At the middle rail two rollers are each mounted by bolts. In the bolt grooves are formed, which serve to accommodate high-temperature-resistant grease or lubricating paste.

adversely in these devices, the lubricant is either chemical is not resistant, in particular not alkali-resistant, for cleaning with aggressive detergents in the longer term to resist and / or when cleaning in a dishwasher washed away would.

Out DE 10 2004 019 104 A1 is a pull-out system for a household appliance, in particular cooking appliance, known with a pull-out system having rolling elements, which are arranged in a rolling element cage, wherein at least the rolling element cage has a lubricant layer. Lubricant particles abraded by the lubricant layer of the rolling element cage can also reach running or sliding surfaces in the extension system that are not in contact with a lubricant layer. Described here is the use of a anorgani's solid lubricant, which is physiologically harmless, in contrast to many other lubricants, such as liquid lubricants of oil or fat, even at high temperatures. Graphite is described here, which can be used even at very high temperatures and is chemically resistant and also cost-effective, as well as molybdenum disulfide, boron nitride and tungsten disulfide. Also disclosed is paint as a binder that holds the lubricant to the rail. Further extension system are in DE 10 2004 019 102 A1 and DE 10 2004 019 103 A1 disclosed.

in this connection is disadvantageous that the applied paint for a sufficient abrasion resistance and chemical resistance must be burned, which comparatively the manufacturing process makes complicated. Complex components are difficult to powder-coat uniformly, and in particular in the area of cut edges and depressions the powder coating weaknesses on.

The The object of the invention is a possibility for a household appliance for permanently good Running or sliding properties at a simpler and cheaper Manufacture, wherein the running or sliding properties preferably by conventional Detergents are largely unaltered and conveniently improves dishwasher safe are.

The object of the invention is achieved by a household appliance, in particular cooking appliance, with the features of patent claim 1 and a pull-out system with the features of the patent Answer 2 solved. According to claim 1 or 2, the coating has at least one polyether ketone, PEK.

Of the the longest known and most important representatives of this group is the polyetheretherketone (PEEK), which is preferably used here. Its melting temperature is 335 ° C. Also included are other descendants the PEK group (e.g., PEEEK, PEEKEK, and PEKK), e.g. B. slightly different Have melting points (e.g., PEKK 391 ° C or PEEEK 324 ° C). polyether ketones are resistant to almost all organic and inorganic chemicals. she are also up to about 280 ° C resistant against hydrolysis. Therefore, PEKs are highly dishwasher safe.

PEKs can also be processed in various ways, eg. B. in shape a dispersion with PEK powder. This can be compared to Lacquer also complex geometries incl. Cutting edges and recesses even, easy and cost-effective coating.

Moreover have PEKs in contrast to paint / binder an excellent Sliding friction coefficient and can be so depending on the load profile ensure a sufficiently low friction even without adding lubricant. This is especially dishwasher-safe advantageous if after several Spülmaschinendurchgängen the Lubricant should be washed out and so the PEK, in particular a PEEK, can take over a "run-flat".

The Material of the contact elements or body is known in the art and may include, for example, metal. By the conventional basic body becomes even at higher Temperatures ensure sufficient mechanical strength, z. B. in ovens at high temperature, z. B. 300 ° C over a longer Period.

The contact elements may be any at least (temporally or locally) partially in contact with each other (eg, rolling, sliding, rolling, rotary contact) elements. For example, they can be parts of a rolling bearing, in particular a cage and rolling elements. Other contact elements may include pairs of rails in sliding contact or pivot bearings and rotary bearings. In particular, in the PEK coating applicable to all components of extraction systems, individually or in combination, such as in DE 10 2004 019 102 A1 and DE 10 2004 019 103 A1 . DE 10 2004 019 104 A1 and DE 38 15 440 are described.

The Task is also solved through a pull-out system for a household appliance, in particular cooking appliance, with the features of claim 2, with a pull-out system, the Having rolling bodies, which are located in a rolling element cage, wherein at least the Wälzkörperkäfig a Has PEK coating. The other components of the extension system, however, can coated with another layer, such as a corrosion protection layer, or uncoated.

It is particularly advantageous if the PEK coating contains PEEK.

It is advantageous for improved lubrication when the PEK coating is on Contains lubricant, In particular, in the case of the aforementioned extraction system can from the PEK layer of the Abrasive body cage abraded Lubricant particles also reach running or sliding surfaces that are not with a PEK coating in contact. This is enough to get one ease of the extract system also there to maintain.

Especially it is preferred if the lubricant is an inorganic solid lubricant is. Such a lubricant is unlike many others Lubricants, such as liquid lubricants from oil or fat, even at high temperatures, such as in an oven, physiologically harmless. It is an advantage if the lubricant is chemically resistant, in particular alkali-resistant, to survive a cleaning in a dishwasher. In this case, the extraction system can continue to be chemically aggressive Media, for example alkalis in a dishwasher, get abandoned.

inorganic Solid lubricants can especially easy to solve from a layer structure. A distributing of the inorganic Solid lubricant on the components, not with the solid lubricant coated, is therefore particularly easy. squeaking or a binding of the extension system are therefore reliably prevented.

It can be advantageous if the lubricant is resistant to high temperatures. In particular, all lubricants which are resistant up to maximum cooking operating temperatures (eg 300 ° C. controller setting + for a short time for 10 minutes temperature peaks of 330 ° C.) are suitable for this purpose. It is particularly preferred if graphite is used as a solid lubricant: graphite can be used even at very high temperatures and is chemically resistant and also inexpensive. Furthermore, molybdenum disulfide can be used as the solid lubricant. In this case, however, it may become problematic at very high temperatures because of the generation of S ₂ . If the manufacturing costs are only of secondary importance, as a solid lubricant and boron nitride is conceivable that in all temperature ranges resistant and is physiologically harmless. The same applies to tungsten disulfide. In order to adjust the abrasion resistance of the rail coating or its layer quality to the requirements, combinations of the abovementioned solid lubricants of graphite, molybdenum disulfide, boron nitride or tungsten disulfide are also conceivable.

to easy introduction of the solid lubricant into the PEK coating this preferably mechanically introduced. This can be easy Way done that a PEK-coated Component in a example with lubricant, eg. Graphite, filled Drum is rotated, causing the lubricant particles in the surface the PEK layer store.

It but also cheap be when the lubricant is incorporated by suspension in the PEK becomes.

The Layer thickness for the PEK coating is at least about 15 μm-20 μm. Lower layer thicknesses are feasible, but not preferred because of the wanted properties the lubrication and especially the abrasion resistance disproportionately with the layer thickness lose weight.

The Lubrication of the extraction system can preferably be provided via a roller cage only, especially lubricant-containing, PEK coating can be achieved. Other components in the extension system, such as rails or rolling elements, must therefore do not take on a lubricating function. The rolling element cage can consist of a mechanically strong material, such as metal, preferably Stole. In this case, the cage on the one hand take over the lubrication of the pull-out system. On the other hand can the rolling element cage too as a stop to limit movement of the moving components be educated. Occurring mechanical loads, for example Wälzkörperkäfige not withstand only plastic or carbon.

The Lubrication of the extraction system can be further improved if in addition to the Wälzkörperkäfig yet at least one further component of the extension system with, in particular lubricant-containing, PEK coating is coated, for example a stationary and / or a movable rail of the extension system. It is particularly preferred if the lubricant-containing PEK coating additionally is applied to a movable rail. By means of the mobile Rail will have an improved distribution of the lubricant in the extraction system reached. The stationary holding rail can with a second Be coated or uncoated layer. In the case, that between the movable puller rail and the fixed one Retaining rail is mounted an intermediate rail, it is convenient if the intermediate rail with the lubricant-containing PEK coating is coated. In this case, the intermediate rail together with the Wälzkörperkäfig both supply the pull-out rail as well as the holding rail with lubricant. In this case, manufacturing technology advantageous to a coating of Retaining rail and / or the extension rail can be omitted. alternative can the outer pull-out rail and / or the stationary inner support rail with a corrosion resistant layer be provided. Manufacturing technology is preferred when the Wälzkörperkäfig, and there in particular the tabs, the contact points to the ball represent, completely coated with the. Compared to a partial coating only the intermediate rail can thus significantly the coating process be simplified.

plays the production cost for applying the PEK coating on the Wälzkörperkäfig or only a minor role on the rail, so it is conceivable Apply several PEK layers with different properties. In this case, a lowermost layer layer can account for a large proportion PEK and accordingly have little solid lubricant. This is secured an abrasion-resistant support of the lubricant on the rail. On the other hand, a topmost layer can have little PEK and a high proportion of solid lubricant exhibit. As a result, the lubricating property z. B. the intermediate rail can be increased.

at several layers or a gradient layer may also be the type or composition of the PEK derivatives depending on the layer depth be different.

Furthermore For example, the PEK coating may contain other fillers, such as ceramics included to adjust its coating quality or abrasion resistance.

According to one another embodiment the extension system be removably mounted in the cooking appliance. In this Case is on the one hand a simple cleaning of the extraction system outside of the cooking appliance reached. On the other hand, example, in a pyrolysis in the cooking appliance The pull-out system will be taken out to avoid the high temperatures suspend in pyrolysis mode.

Preferably, the Wälzkörperkäfig can be arranged in a cavity of the movable components or the rails of the extension system, whereby the Wälzkörperkäfig is protected from contamination. Therefore, the Wälzkörperkäfig even one, in particular lubricant-containing, PEK Be Although it has an excellent lubricating property, it is difficult to clean due to its adhesive properties.

embodiment

following are two embodiments of the Invention with reference to the attached Figures described. Show it:

1 according to the first embodiment, an extension system in a cooking appliance;

2 in a sectional view of the extension system of the cooking appliance;

3 a ball cage of the extension system; and

4 According to a second embodiment of an enlarged section of an extension system.

In the 1 is according to the first embodiment, a cooking appliance with a cooking appliance muffle 1 shown, which limits a cooking space. The cooking appliance has a hinged door 3 for closing a front muffle opening 5 on. In the 1 is the swing gate 3 shown in an open state. On opposite side walls 9 the cooking appliance muffle 1 are corresponding lateral guide rods 11 and a pull-out system, consisting of two opposite the telescopic extensions 13 , held. The telescopic extensions 13 are removably supported in a top of four horizontal cooking levels. In each of the three levels below, there are the corresponding guide rods 11 removably supported. On the two corresponding bottom guide rods 11 is supported by a baking sheet 13 partly from the cooking appliance muffle 1 is pushed out. The guide rods 11 are mufflefrontseitig each in a bearing bush 15 plugged in. This is in a mounting opening of the muffle side wall 9 assembled. The telescopic extensions 13 are with a holding plate 14 formed, each in an annular groove 16 the bearing bush 15 is mounted. In the area of a muffle back wall 17 are the guide rods 11 as well as the telescopic extensions 13 each in a mounting hole 19 stored. Both the guide rods 11 as well as the telescopic extensions 13 are tool-free by a user from the muffle 1 to solve.

The present system is the pull-out system 13 designed as a telescopic extension. The telescopic extension 13 is according to the 2 in one in the 1 shown viewing direction 1 shown in cross section. The telescopic extension 13 has a lower retaining rail 23 on that over the retaining plate 14 fixed to the muffle side wall 9 is held.

Both the retaining plate 14 as well as the bearing bush 15 are in the 2 shown with dashed lines. In addition to the stationary holding rail 23 exists the telescopic extension 13 from a movable intermediate rail 25 as well as a likewise movable pull-out rail 27 , The intermediate rail 25 is about bullets 29 between the pull-out rail 27 and the stationary retaining rail 23 stored.

The design of the rails 23 . 25 . 27 is not limited to the present embodiment. So the retaining rail 23 also like a round rod 11 be educated. On the retaining rail 23 the pull-out rail can also be guided via other rolling elements. In this case, the design of the pull-out rail 27 not limited to the present embodiment. Rather, the drawer rail 27 be designed as a sled, a runner or other extract element. Between the extract element 27 and the retaining rail 23 can also on the arrangement of the intermediate rail 25 be waived.

The retaining rail 23 and the pull-out rail 27 exist according to the 2 from mutually identically formed U-profile parts made of an uncoated sheet steel. The two rails 23 . 27 are arranged with their open sides facing each other. They limit a substantially closed cavity 31 in which the intermediate rail 25 is arranged. This means that at least in the retracted state of the telescopic extension 13 the intermediate rail 25 almost completely from the pull-out rail 27 and the retaining rail 23 is enclosed. Fats, soiling or the like are therefore from the balls 29 and from the intermediate rail 25 kept away.

In order to allow a smooth pulling out and pushing together of the extension system, is the intermediate rail 25 with a lubricant-containing PEEK layer 33 coated. The lubricant-containing PEEK layer 33 is in the 2 shown in exaggerated layer thickness. The layer thickness is realistically in a range of at least between 15 and 20 microns. In contrast to the intermediate rail 33 are both the balls 29 as well as the retaining rail 23 and the pull-out rail 27 not with the lubricant-containing PEEK layer 33 coated but uncoated. This will cause the bullets to run 29 on the one hand on the lubricant-containing PEEK layer 33 the intermediate rail 25 and on the other hand on the uncoated running surfaces of the retaining rail 23 and the pull-out rail 27 ,

The surface properties of the metal surface of the balls 29 , the holding rail 23 as well as the pull-out rail 27 on the one hand and the lubrication containing PEEK layer 33 on the other hand are different. Due to these different surface properties results in a particularly good rolling behavior of the balls 29 and thus good running properties of the extension system.

Alternatively, the retaining rail 23 and / or the pull-out rail 27 be coated with a second layer, as in the 2 with the reference number 34 indicated by dashed line. The two different layers 33 and 34 have different surface properties. In particular, with a different surface hardness, the rolling behavior of the ball 29 be improved. The second layer 34 may be formed as a corrosion resistant layer.

In the present case, the lubricant-containing PEEK layer 33 Particles of an inorganic solid lubricant, such as graphite on. For the production of the lubricant layer 33 First, a powder of the inorganic solid lubricant is suspended in PEEK and then the intermediate rail 25 coated.

by virtue of the very good flow properties (all Areas including Cut edges are reached), the PEEK suspension can be uniformly applied and then heat treated, wherein the PEEK particles merge to form a PEEK layer.

The lubricant-containing PEEK layer 33 the intermediate rail 25 is enough, even between the balls 29 and the pull-out rail 27 or the retaining rail 23 to introduce enough lubricant. The in the 2 illustrated U-profile-shaped rails 23 . 27 are particularly well suited, the intermediate rail 33 to protect against contamination. In the in the 2 it is sufficient to use the lubricants-containing PEEK layer 33 only with regard to their lubricating properties.

According to the 2 are the balls 29 in two opposite ball cages 37 arranged. The balls 29 are in the ball cages 37 rotatably supported. One of the ball cages 37 in the 3 shown. The ball cage 37 consists of a thin sheet steel, which leads to an angular part with three in the profile trapezoidally arranged sides 39 is shaped. In each of the pages 39 are recesses 41 cut out. The recesses 41 are each page 39 arranged in two consecutive rows. The two rows are over a middle section 43 of the ball cage 37 are spaced. Every recess 41 is partly from an angled embossed edge 45 limited, the ball 29 in the recess 41 holds. At one of the ball 29 facing side has the angled embossing edge 45 an abrasion surface 46 on.

The in the 2 and 3 shown ball cages 37 are with the lubricant-containing PEEK layer 33 coated. In the 2 is the one on the ball cage 37 applied lubricant-containing PEEK layer 33 indicated by dashed line. In the 3 is the one on the ball cage 37 applied lubricant-containing PEEK layer 33 indicated in hatching. This may be due to the rotation of the balls 29 at the abrasion surface 46 of the angled stamping edge 45 a slight lubricant abrasion can be generated. The abrasion is caused by the adjustment movement of the telescopic extension 13 along the treads of the rails 25 . 23 . 27 distributed. As a result, the pull-out behavior of the extension system is permanently improved. Furthermore, squeaking noises or sluggishness in the operation of the telescopic extension are effectively reduced. The application of the lubricant-containing PEEK layer 33 on the ball cage 37 takes place as the application of the lubricant-containing PEEK layer 33 on the respective rail.

The ball cages 37 are between the rails 23 . 25 . 27 freely movable in the longitudinal direction. The front ends 47 every ball cage 37 serve in the in the 2 shown telescopic extension 13 as stops, which is a longitudinal movement of the rails 23 . 25 . 27 limit. The telescopic extension 13 can therefore be pulled apart until the end faces 47 of the ball cage 37 come in contact with corresponding, not shown rail attacks.

The power flow at the stop via an embossing in the rail 23 on balls 29 from there to the cage 37 , From the cage 37 the power flow continues on other balls 29 and on this further to an imprint in the rail 25 , About imprints in the rail 25 the force flows over balls 29 in the next cage 37 , From the cage 37 over the balls 29 in imprints of the rail 27 ,

In the 4 is shown in a second embodiment, an enlarged section of a pull-out system in which the ball cage 37 is alternatively configured. Shown are the intermediate rail 25 and the retaining rail 23 that over in the ball cage 37 supported balls 29 are slidably mounted. In contrast to 3 is the angled margin 45 every recess 41 designed as a raised collar. The raised collar 45 is formed as a cylinder portion or sleeve portion, which is the ball 29 completely relocates. This is compared to the 3 the ball 29 available abrasion surface 46 of the ball cage 37 increased. Due to the rotation of the balls 29 Therefore, a larger amount of lubricant can be removed from the ball cage, which is the extraction system for lubrication available.

Of course it is the invention is not limited to the exemplary drawer system shown limited, but can be applied to all relatively moving, contacting devices be applied.

1

cooking appliance muffle

3

hinged door

5

front muffle opening

9

side walls

11

guide bars

13

telescopic shelves

14

Retaining plate

15

bearing bush

16

ring groove

17

Muffle rear wall

19

mounting hole

23

retaining rail

25

intermediate rail

27

pull-out rail

29

roll

31

cavity

33

PEEK layer

34

second layer

37

ball cages

39

pages

41

recesses

43

midsection

45

embossing edge

46

abrasion area

47

front sides

Claims (13)

Household appliance, in particular cooking appliance, comprising at least two mutually relatively movable contact elements ( 29 . 37 ) which are at least partially in contact with each other, wherein at least one contact element is a coating ( 33 ), characterized in that the coating ( 33 ) has at least one polyether ketone, PEK. Extractor system for a household appliance, the extract system ( 13 ) Rolling elements ( 29 ) in a Wälzkörperkäfig ( 37 ) are arranged, wherein at least the Wälzkörperkäfig ( 37 ) a coating ( 33 ), characterized in that the coating ( 33 ) has at least one polyether ketone, PEK. Device according to claim 1 or 2, characterized in that the PEK coating ( 33 ) Contains PEEK. Device according to one of the preceding claims, characterized in that the PEK coating ( 33 ) contains a lubricant. Device according to claim 4, characterized in that the lubricant comprises an inorganic solid lubricant. Device according to claim 5, characterized in that that the solid lubricant graphite, molybdenum disulfide, boron nitride and / or Has tungsten disulfide. Device according to one of claims 5 or 6, characterized in that the solid lubricant in the PEK coating ( 33 ) has been introduced mechanically. Device according to one of the preceding claims, characterized in that the PEK coating ( 33 ) is formed at least partially multi-layered. Device according to one of the preceding claims, characterized in that the PEK coating ( 33 ) contains further fillers, such as ceramic. Pull-out system according to one of Claims 2 to 9, characterized in that the pull-out system ( 13 ) is removably mounted in the household appliance. Pull-out system according to one of claims 2 to 10, characterized in that at least one, in particular first, pull-out element ( 25 ) of the extraction system ( 13 ) with the PEK coating ( 33 ) is coated. Pull-out system according to one of claims 2 to 11, characterized in that the pull-out element is an intermediate rail ( 25 ), which is located between a stationary support rail ( 23 ) and a pull-out rail ( 27 ) for holding a food support ( 13 ) is stored. Device according to one of the preceding claims, characterized in that a layer thickness of the PEK coating ( 33 ) is at least 15 microns.